Virtual Journal of Atomic Quantum Fluids

Quantum simulation of frustrated Ising spins with trapped ions

K. Kim, M.-S. Chang, S. Korenblit, R. Islam, E. E. Edwards et al.
A network is frustrated when competing interactions between nodes prevent each bond from being satisfied. This compromise is central to the behaviour of many complex systems, from social and neural networks to protein folding and magnetism. Frustrated networks have highly degenerate ground states, ... [Nature 465, 590 (2010)] published Thu Jun 3, 2010.

Electromagnetically induced transparency with single atoms in a cavity

Martin Mcke, Eden Figueroa, Joerg Bochmann, Carolin Hahn, Karim Murr et al.
Optical nonlinearities offer unique possibilities for the control of light with light. A prominent example is electromagnetically induced transparency (EIT), where the transmission of a probe beam through an optically dense medium is manipulated by means of a control beam. Scaling such experiments ... [Nature 465, 755 (2010)] published Thu Jun 10, 2010.

Hawking Radiation from an Acoustic Black Hole on an Ion Ring

B. Horstmann, B. Reznik, S. Fagnocchi, and J. I. Cirac
In this Letter we propose to simulate acoustic black holes with ions in rings. If the ions are rotating with a stationary and inhomogeneous velocity profile, regions can appear where the ion velocity exceeds the group velocity of the phonons. In these regions phonons are trapped like light in black ... [Phys. Rev. Lett. 104, 250403 ] published .

Cloaking spin-(1/2) matter waves

De-Hone Lin
A physical construct for the cloaking of relativistic spin-(1/2) matter waves is proposed. It is shown that when the effective energy and mass of relativistic spin-(1/2) particles moving in an effective vector field in a spherical shell are controlled, their matter waves can be perfectly guided thro ... [Phys. Rev. A 81, 063640 ] published .

Thermodynamic instability and first-order phase transition in an ideal Bose gas

Jeong-Hyuck Park and Sang-Woo Kim
We conduct a rigorous investigation into the thermodynamic instability of an ideal Bose gas confined in a cubic box, without assuming a thermodynamic limit or a continuous approximation. Based on the exact expression of the canonical partition function, we perform numerical computations up to 10 par ... [Phys. Rev. A 81, 063636 ] published .

A dynamic correspondence between BoseEinstein condensates and FriedmannLemaitreRobertsonWalker and Bianchi I cosmology with a cosmological constant

Jennie D'Ambroise and Floyd L. Williams
In some interesting work of James Lidsey, the dynamics of FriedmannLemaitreRobertsonWalker (FLRW) cosmology with positive curvature and a perfect fluid matter source is shown to be modeled in terms of a time-dependent, harmonically trapped BoseEinstein condensate. In the present work, we extend this ... [J. Math. Phys. 51, 062501 (2010)] published Wed Jun 2, 2010.

Many-body approach for quartet condensation in strong coupling

Takaaki Sogo, Gerd Ropke, and Peter Schuck
The theory for condensation of higher fermionic clusters is developed. Fully self-consistent nonlinear equations for the quartet order parameter in strongly coupled fermionic systems are established and solved. The breakdown of the quasiparticle picture is pointed out. Derivation of numerically trac ... [Phys. Rev. C 81, 064310 ] published .

Dielectric properties of classical and quantized ionic fluids

Johan S. Hoye
We study time-dependent correlation functions of classical and quantum gases using methods of equilibrium statistical mechanics for systems of uniform as well as nonuniform densities. The basis for our approach is the path integral formalism of quantum mechanical systems. With this approach the stat ... [Phys. Rev. E 81, 061114 ] published .

Universality of Brunnian (N-body Borromean) four- and five-body systems

M. T. Yamashita, D. V. Fedorov, and A. S. Jensen
We compute binding energies and root-mean-square radii for weakly bound systems of N=4 and 5 identical bosons. Ground and first excited states of an N-body system appear below the threshold for binding the system with N-1 particles. Their root-mean-square radii approach constants in the limit of wea ... [Phys. Rev. A 81, 063607 ] published .

Quantum quench dynamics of the sine-Gordon model in some solvable limits

A Iucci and M Cazalilla
With regard to the thermalization problem in isolated quantum systems, we investigate the dynamics following a quantum quench of the sine-Gordon model (sGM) in the LutherEmery and the semiclassical limits. We consider the quench from the gapped to the gapless phase, as well as the reverse one. By ob ... [New J. Phys. 12, 055019 (2010)] published Wed Jun 2, 2010.

Benchmarking the variational cluster approach by means of the one-dimensional Bose-Hubbard model

Michael Knap, Enrico Arrigoni, and Wolfgang von der Linden
Convergence properties of the variational cluster approach with respect to the variational parameter space, cluster size, and boundary conditions of the reference system are investigated and discussed for bosonic many-body systems. Specifically, the variational cluster approach is applied to the one ... [Phys. Rev. B 81, 235122 ] published .

Direct energy cascade in two-dimensional compressible quantum turbulence

Ryu Numasato, Makoto Tsubota, and Victor S. L'vov
We numerically study two-dimensional quantum turbulence with a Gross-Pitaevskii model. With the energy initially accumulated at large scale, quantum turbulence with many quantized vortex points is generated. Due to the lack of enstrophy conservation in this model, direct energy cascade with a Kolmog ... [Phys. Rev. A 81, 063630 ] published .

Wentzel-Kramers-Brillouin approach and quantum corrections to classical dynamics in the Josephson problem

Felix Nissen and Jonathan Keeling
We apply a many-body Wentzel-Kramers-Brillouin (WKB) approach to determine the leading quantum corrections to the semiclassical dynamics of the Josephson model, describing interacting bosons able to tunnel between two localized states. The semiclassical dynamics is known to divide between regular os ... [Phys. Rev. A 81, 063628 ] published .

Direct absorption imaging of ultracold polar molecules

D. Wang, B. Neyenhuis, M. H. G. de Miranda, K.-K. Ni, S. Ospelkaus et al.
We demonstrate a scheme for direct absorption imaging of an ultracold ground-state polar molecular gas near quantum degeneracy. Imaging molecules without closed optical cycling transitions is challenging. Our technique relies on photon-shot-noise-limited absorption imaging on a strong but open bound ... [Phys. Rev. A 81, 061404 ] published .

Rb tunable-interaction BoseEinstein condensate machine

P. A. Altin, N. P. Robins, D. Doring, J. E. Debs, R. Poldy et al.
We describe our experimental setup for creating stable BoseEinstein condensates (BECs) of Rb with tunable interparticle interactions. We use sympathetic cooling with Rb in two stages, initially in a tight IoffePritchard magnetic trap and subsequently in a weak, large-volume, crossed optical dipole t ... [Rev. Sci. Instrum. 81, 063103 (2010)] published Wed Jun 9, 2010.

Reactions of ultracold alkali-metal dimers

Piotr S. Zuchowski and Jeremy M. Hutson
We investigate the energetics of reactions involving pairs of alkali-metal dimers. Atom exchange reactions to form homonuclear dimers are energetically allowed for some but not all of the heteronuclear dimers. We carry out high-level electronic structure calculations on the potential energy surfaces ... [Phys. Rev. A 81, 060703 ] published .

Zeeman relaxation of cold atomic iron and nickel in collisions with He

Cort Johnson, Bonna Newman, Nathan Brahms, John M. Doyle, Daniel Kleppner et al.
We have measured the ratio gamma of the diffusion cross section to the angular momentum reorientation cross section in the colliding Fe-He and Ni-He systems. Nickel (Ni) and iron (Fe) atoms are introduced via laser ablation into a cryogenically cooled experimental cell containing cold (<1 K) He buff ... [Phys. Rev. A 81, 062706 ] published .

Self-organization in two-dimensional swarms

Jihad R. Touma, Amer Shreim, and Leonid I. Klushin
We undertake a systematic numerical exploration of self-organized states in a deterministic model of interacting self-propelled particles in two dimensions. In the process, we identify various types of collective motion, namely, disordered swarms, rings, and droplets. We construct a phase diagram, w ... [Phys. Rev. E 81, 066106 ] published .

Collective Lamb Shift in Single-Photon Superradiance

Ralf Rhlsberger, Kai Schlage, Balaram Sahoo, Sebastien Couet, and Rudolf Rffer
Superradiance, the cooperative spontaneous emission of photons from an ensemble of identical atoms, provides valuable insights into the many-body physics of photons and atoms. We show that an ensemble of resonant atoms embedded in the center of a planar cavity can be collectively excited by synchrot ... [Science 328, 1248 ] published .

Quantum phase transitions in an interacting atom-molecule boson model

G. Santos, A. Foerster, J. Links, E. Mattei, and S. R. Dahmen
We study the quantum phase transitions of a model that describes the interconversion of interacting bosonic atoms and molecules. Using a classical analysis, we identify a threshold coupling line separating a molecular phase and a mixed phase. Through studies of the energy gap, von Neumann entangleme ... [Phys. Rev. A 81, 063621 ] published .

Spatially resolved excitation of Rydberg atoms and surface effects on an atom chip

Atreju Tauschinsky, Rutger M. T. Thijssen, S. Whitlock, H. B. van Linden van den Heuvell, and R. J. C. Spreeuw
We demonstrate spatially resolved, coherent excitation of Rydberg atoms on an atom chip. Electromagnetically induced transparency (EIT) is used to investigate the properties of the Rydberg atoms near the gold-coated chip surface. We measure distance-dependent shifts (~10 MHz) of the Rydberg energy l ... [Phys. Rev. A 81, 063411 ] published .

Impossibility of faithfully storing single photons with the three-pulse photon echo

Nicolas Sangouard, Christoph Simon, Jiri Minar, Mikael Afzelius, Thierry Chaneliere et al.
The three-pulse photon echo is a well-known technique to store intense light pulses in an inhomogeneously broadened atomic ensemble. This protocol is attractive because it is relatively simple and it is well suited for the storage of multiple temporal modes. Furthermore, it offers very long storage ... [Phys. Rev. A 81, 062333 ] published .

Generation of macroscopic singlet states in atomic ensembles

Geza Toth and Morgan W Mitchell
We study squeezing of the spin uncertainties by quantum non-demolition (QND) measurement in non-polarized spin ensembles. Unlike the case of polarized ensembles, the QND measurements can be performed with negligible back-action, which allows, in principle, perfect spin squeezing as quantified by Tot ... [New J. Phys. 12, 053007 (2010)] published Wed Jun 2, 2010.

Continuous-variable entanglement purification with atomic systems

Stojan Rebic, Stefano Mancini, Giovanna Morigi, and David Vitali
We present a proposal for entanglement purification of the continuous-variable quantum state of two propagating optical fields. The scheme is based on each field interacting with a local node-atomic ensemble whose internal collective excitation plays the role of an ancillary continuous-variable reso ... [J. Opt. Soc. Am. B 27, A198 (2010)] published Wed Jun 16, 2010.

Particle entanglement in rotating gases

Zhao Liu and Heng Fan
In this paper, we investigate the particle entanglement in two-dimensional (2D) weakly interacting rotating Bose and Fermi gases. We find that both particle localization and vortex localization can be indicated by particle entanglement. We also use particle entanglement to show the occurrence of edg ... [Phys. Rev. A 81, 062302 ] published .

Orientation-Dependent Entanglement Lifetime in a Squeezed Atomic Clock

Ian D. Leroux, Monika H. Schleier-Smith, and Vladan Vuletic
We study experimentally the application of a class of entangled states, squeezed spin states, to the improvement of atomic-clock precision. In the presence of anisotropic noise, the entanglement lifetime is strongly dependent on squeezing orientation. We measure the Allan deviation spectrum of a clo ... [Phys. Rev. Lett. 104, 250801 ] published .

Cold-Atom-Induced Control of an Optomechanical Device

M. Paternostro, G. De Chiara, and G. M. Palma
We consider a cavity with a vibrating end mirror and coupled to a Bose-Einstein condensate. The cavity field mediates the interplay between mirror and collective oscillations of the atomic density. We study the implications of this dynamics and the possibility of an indirect diagnostic. Our predicti ... [Phys. Rev. Lett. 104, 243602 ] published .

Atom lithography with near-resonant standing waves

R. Arun, Offir Cohen, and I. Sh. Averbukh
We study the optimal focusing of two-level atoms with a near-resonant standing wave light, using both classical and quantum treatments of the problem in the thin- and thick-lens regimes. It is found that the near-resonant standing wave focuses the atoms with a reduced background in comparison with f ... [Phys. Rev. A 81, 063809 ] published .

Classical phase-space approach for coherent matter waves

Francois Impens and David Guery-Odelin
We investigate a classical phase-space approach of matter-wave propagation based on the truncated Wigner equation (TWE). We show that such a description is suitable for ideal matter waves in quadratic time-dependent confinement as well as for harmonically trapped Bose-Einstein condensates in the Tho ... [Phys. Rev. A 81, 065602 ] published .

Coherent control of quantum tunneling in different driving-frequency regions

Gengbiao Lu, Wenhua Hai, Honghua Zhong, and Qiongtao Xie
We investigate the coherent control of quantum tunneling for a single particle held in a driven double-well potential. For a moderate-frequency region, we demonstrate that the irregular quantum tunneling is associated with classically chaotic dynamics. A set of lower resonance-like frequencies is fo ... [Phys. Rev. A 81, 063423 ] published .

Correlation dynamics after short-pulse photoassociation

Christiane P. Koch and Ronnie Kosloff
Two atoms in an ultracold gas are correlated at short interatomic distances due to threshold effects in which the potential energy of their interaction dominates the kinetic energy. The correlations manifest themselves in a distinct nodal structure of the density matrix at short interatomic distance ... [Phys. Rev. A 81, 063426 ] published .

Ultracold Giant Polyatomic Rydberg Molecules: Coherent Control of Molecular Orientation

Seth T. Rittenhouse and H. R. Sadeghpour
We predict the existence of a class of ultracold giant molecules formed from trapped ultracold Rydberg atoms and polar molecules. The interaction which leads to the formation of such molecules is the anisotropic, long-range charge-dipole interaction. We show that prominent candidate molecules such a ... [Phys. Rev. Lett. 104, 243002 ] published .

Nonlinear Phase Dynamics in a Driven Bosonic Josephson Junction

Erez Boukobza, Michael G. Moore, Doron Cohen, and Amichay Vardi
We study the collective dynamics of a driven two-mode Bose-Hubbard model in the Josephson interaction regime. The classical phase space is mixed, with chaotic and regular components, which determine the dynamical nature of the fringe visibility. For a weak off-resonant drive, where the chaotic compo ... [Phys. Rev. Lett. 104, 240402 ] published .

Rotational response of two-component Bose-Einstein condensates in ring traps

P. L. Halkyard, M. P. A. Jones, and S. A. Gardiner
We consider a two-component Bose-Einstein condensate in a ring trap in a rotating frame and show how to determine the response of such a configuration to being in a rotating frame via accumulation of a Sagnac phase. This may be accomplished through either population oscillations or the motion of spa ... [Phys. Rev. A 81, 061602 ] published .

Bogoliubov theory and Lee-Huang-Yang corrections in spin-1 and spin-2 Bose-Einstein condensates in the presence of the quadratic Zeeman effect

Shun Uchino, Michikazu Kobayashi, and Masahito Ueda
We develop Bogoliubov theory of spin-1 and spin-2 Bose-Einstein condensates (BECs) in the presence of a quadratic Zeeman effect, and derive the Lee-Huang-Yang (LHY) corrections to the ground-state energy, pressure, sound velocity, and quantum depletion. We investigate all the phases of spin-1 and sp ... [Phys. Rev. A 81, 063632 ] published .

Collapse dynamics of a Yb-Yb Bose-Einstein condensate

G. K. Chaudhary and R. Ramakumar
In this paper, we present a theoretical study of a two-component Bose-Einstein condensate composed of ytterbium (Yb) isotopes in a three-dimensional anisotropic harmonic potential. The condensate consists of a mixture of Yb atoms which have a negative s-wave scattering length and Yb atoms having a p ... [Phys. Rev. A 81, 063603 ] published .

Phase separation and pairing regimes in the one-dimensional asymmetric Hubbard model

L. Barbiero, M. Casadei, M. Dalmonte, C. Degli Esposti Boschi, E. Ercolessi et al.
We address some open questions regarding the phase diagram of the one-dimensional Hubbard model with asymmetric hopping coefficients and balanced species. In the attractive regime we present a numerical study of the passage from on-site pairing dominant correlations at small asymmetries to charge-de ... [Phys. Rev. B 81, 224512 ] published .

Spin dynamics and domain formation of a spinor Bose-Einstein condensate in an optical cavity

Lu Zhou, Han Pu, Hong Y. Ling, Keye Zhang, and Weiping Zhang
We consider a ferromagnetic spin-1 Bose-Einstein condensate (BEC) dispersively coupled to a unidirectional ring cavity. We show that the ability of the cavity to modify, in a highly nonlinear fashion, matter-wave phase shifts adds an additional dimension to the study of spinor condensates. In additi ... [Phys. Rev. A 81, 063641 ] published .

Spin textures in condensates with large dipole moments

J. A. M. Huhtamaki, M. Takahashi, T. P. Simula, T. Mizushima, and K. Machida
We have solved numerically the ground states of a Bose-Einstein condensate in the presence of dipolar interparticle forces using a semiclassical approach. Our motivation is to model, in particular, the spontaneous spin textures emerging in quantum gases with large dipole moments, such as Cr or Dy co ... [Phys. Rev. A 81, 063623 ] published .

Unconventional superfluidity of fermions in Bose-Fermi mixtures

O. Dutta and M. Lewenstein
We examine a two-dimensional mixture of single-component fermions and dipolar bosons. We calculate the self-enregies of the fermions in the normal state and the Cooper-pair channel by including first-order vertex correction to derive a modified Eliashberg equation. We predict the appearance of super ... [Phys. Rev. A 81, 063608 ] published .

Collective excitations of the hybrid atomic-molecular Bose-Einstein condensates

Moumita Gupta and Krishna Rai Dastidar
We investigate the low-energy excitations of the spherically and axially trapped atomic Bose-Einstein condensate coupled to a molecular Bose gas by coherent Raman transitions. We apply the sum-rule approach of many-body response theory to derive the low-lying collective excitation frequencies of the ... [Phys. Rev. A 81, 063631 ] published .

Bose-Einstein condensates on slightly asymmetric double-well potentials

B. Julia-Diaz, J. Martorell, and A. Polls
An analytical insight into the symmetry-breaking mechanisms underlying the transition from Josephson to self-trapping regimes in Bose-Einstein condensates is presented. We obtain expressions for the ground-state properties of the system of a gas of attractive bosons modeled by a two-site Bose-Hubbar ... [Phys. Rev. A 81, 063625 ] published .

Pipelike current-carrying vortices in two-component condensates

M. N. Chernodub and A. S. Nedelin
We study straight vortices with global longitudinal currents in the Bogomolny limit of the Abelian Higgs model with two charged scalar fields. The model possesses global SU(2) and local electromagnetic U(1) symmetries spontaneously broken to a global U(1) group, and corresponds to a semilocal limit ... [Phys. Rev. D 81, 125022 ] published .

Spatial pattern formation and polarization dynamics of a nonequilibrium spinor polariton condensate

Magnus O. Borgh, Jonathan Keeling, and Natalia G. Berloff
Quasiparticles in semiconductorssuch as microcavity polaritonscan form condensates in which the steady-state density profile is set by the balance of pumping and decay. By taking account of the polarization degree of freedom for a polariton condensate, and considering the effects of an applied magne ... [Phys. Rev. B 81, 235302 ] published .

Quench dynamics near a quantum critical point: Application to the sine-Gordon model

C. De Grandi, V. Gritsev, and A. Polkovnikov
We discuss the quench dynamics near a quantum critical point focusing on the sine-Gordon model as a primary example. We suggest a unified approach to sudden and slow quenches, where the tuning parameter lambda(t) changes in time as lambda(t)~upsilont, based on the adiabatic expansion of the excitati ... [Phys. Rev. B 81, 224301 ] published .

Two-mode Bose gas: Beyond classical squeezing

C. Bodet, J. Esteve, M. K. Oberthaler, and T. Gasenzer
The dynamical evolution of squeezing correlations in an ultracold Bose-Einstein condensate distributed across two modes is investigated theoretically in the framework of the Bose-Hubbard model. It is shown that the eigenstates of the Hamiltonian do not exploit the full region allowed by Heisenberg's ... [Phys. Rev. A 81, 063605 ] published .

Multiple atomic dark solitons in cigar-shaped Bose-Einstein condensates

G. Theocharis, A. Weller, J. P. Ronzheimer, C. Gross, M. K. Oberthaler et al.
We consider the stability and dynamics of multiple dark solitons in cigar-shaped Bose-Einstein condensates. Our study is motivated by the fact that multiple matter-wave dark solitons may naturally form in such settings as per our recent work [Phys. Rev. Lett. 101, 130401 (2008)]. First, we study the ... [Phys. Rev. A 81, 063604 ] published .

Exact solutions of the Gross-Pitaevskii equation for stable vortex modes in two-dimensional Bose-Einstein condensates

Lei Wu (吴雷), Lu Li, Jie-Fang Zhang, Dumitru Mihalache, Boris A. Malomed et al.
We construct exact solutions of the Gross-Pitaevskii equation for solitary vortices, and approximate ones for fundamental solitons, in two-dimensional models of Bose-Einstein condensates with a spatially modulated nonlinearity of either sign and a harmonic trapping potential. The number of vortex-so ... [Phys. Rev. A 81, 061805 ] published .

Anderson localization of a Tonks-Girardeau gas in potentials with controlled disorder

J. Radic, V. BaCic, D. Jukic, M. Segev, and H. Buljan
We theoretically demonstrate features of Anderson localization in a Tonks-Girardeau gas confined in one-dimensional potentials with controlled disorder. That is, we investigate the evolution of the single-particle density and correlations of a Tonks-Girardeau wave packet in such disordered potential ... [Phys. Rev. A 81, 063639 ] published .

Dynamics of macroscopic tunneling in elongated Bose-Einstein condensates

G. Dekel, V. Farberovich, V. Fleurov, and A. Soffer
We investigate macroscopic tunneling from an elongated quasi-one-dimensional trap, forming a cigar-shaped Bose-Einstein condensate (BEC). Using a recently developed formalism we get the leading analytical approximation for the right-hand side of the potential wall, i.e., outside the trap, and a form ... [Phys. Rev. A 81, 063638 ] published .

Ground states of spin-2 condensates in an external magnetic field

G.-P. Zheng, Y.-G. Tong, and F.-L. Wang
The possible ground states of spin-2 Bose-Einstein condensates in an external magnetic field are obtained analytically and classified systematically according to the population of the condensed atoms at the hyperfine sublevels. It is shown that the atoms can populate simultaneously at four hyperfine ... [Phys. Rev. A 81, 063633 ] published .

Solitary waves in mixtures of Bose gases confined in annular traps

J. Smyrnakis, M. Magiropoulos, G. M. Kavoulakis, and A. D. Jackson
A two-component Bose-Einstein condensate that is confined in a one-dimensional ring potential supports solitary-wave solutions, which we evaluate analytically in the limit of a large ring. The derived solutions are shown to be unique. The corresponding dispersion relation that generalizes the case o ... [Phys. Rev. A 81, 063601 ] published .

Rotating three-dimensional solitons in Bose-Einstein condensates with gravitylike attractive nonlocal interaction

F. Maucher, S. Skupin, M. Shen, and W. Krolikowski
We study formation of rotating three-dimensional high-order solitons (azimuthons) in Bose Einstein condensate with attractive nonlocal nonlinear interaction. In particular, we demonstrate formation of toroidal rotating solitons and investigate their stability. We show that variational methods allow ... [Phys. Rev. A 81, 063617 ] published .

Dynamics of inhomogeneous condensates in contact with a surface

Yu. V. Bludov, Zhenya Yan, and V. V. Konotop
We show that interplay of linear attractive (repulsive) boundary with inhomogeneous repulsive (attractive) interatomic interactions results in nonlinear localized surface modes (surface solitons), some of which are stable. We consider several example systems describing interaction of inhomogeneous B ... [Phys. Rev. A 81, 063610 ] published .

Interacting Hofstadter Spectrum of Atoms in an Artificial Gauge Field

Stephen Powell, Ryan Barnett, Rajdeep Sensarma, and Sankar Das Sarma
Motivated by experimental advances in the synthesis of gauge potentials for ultracold atoms, we consider the superfluid phase of interacting bosons on a square lattice in the presence of a magnetic field. We show that superfluid order implies spatial symmetry breaking, and predict clear signatures o ... [Phys. Rev. Lett. 104, 255303 ] published .

Stroboscopic Generation of Topological Protection

C. M. Herdman, Kevin C. Young, V. W. Scarola, Mohan Sarovar, and K. B. Whaley
Trapped neutral atoms offer a powerful route to robust simulation of complex quantum systems. We present here a stroboscopic scheme for realization of a Hamiltonian with n-body interactions on a set of neutral atoms trapped in an addressable optical lattice, using only 1- and 2-body physical operati ... [Phys. Rev. Lett. 104, 230501 ] published .

Creffield and Sols Reply:

C. E. Creffield and F. Sols
A Reply to the Comment by G. Benenti et al. ... [Phys. Rev. Lett. 104, 228902 ] published .

Comment on Coherent Ratchets in Driven Bose-Einstein Condensates

G. Benenti, G. Casati, S. Denisov, S. Flach, P. Hanggi et al.
A Comment on the Letter by C. E. Creffield and F. Sols, Phys. Rev. Lett. 103, 200601 (2009). The authors of the Letter offer a Reply. ... [Phys. Rev. Lett. 104, 228901 ] published .

Mishmash and Carr Reply:

R. V. Mishmash and L. D. Carr
A Reply to the Comment by Jacek Dziarmaga, Piotr Deuar, and Krzysztof Sacha. ... [Phys. Rev. Lett. 105, 018904 ] published .

Comment on Quantum Entangled Dark Solitons Formed by Ultracold Atoms in Optical Lattices

Jacek Dziarmaga, Piotr Deuar, and Krzysztof Sacha
A Comment on the Letter by R. V. Mishmash and L. D. Carr, Phys. Rev. Lett. 103, 140403 (2009). The authors of the Letter offer a Reply. ... [Phys. Rev. Lett. 105, 018903 ] published .

Thermometry with spin-dependent lattices

D McKay and B DeMarco
We propose a method for measuring the temperature of strongly correlated phases of ultracold atom gases confined in spin-dependent optical lattices. In this technique, a small number of `impurity' atomstrapped in a state that does not experience the lattice potentialare in thermal contact with atoms ... [New J. Phys. 12, 055013 (2010)] published Wed Jun 2, 2010.

Probing Kitaev models on small lattices

Han-Dong Chen, B. Wang, and S. Das Sarma
We address the following important question: how to distinguish Kitaev models experimentally realized on small lattices from other nontopological interacting spin models. Based on symmetry arguments and exact diagonalization, we show that a particularly characteristic pattern of spin-spin correlatio ... [Phys. Rev. B 81, 235131 ] published .

Interaction-induced fractional Bloch and tunneling oscillations

Ramaz Khomeriki, Dmitry O. Krimer, Masudul Haque, and Sergej Flach
We study the dynamics of few interacting bosons in a one-dimensional lattice with dc bias. In the absence of interactions the system displays single-particle Bloch oscillations. For strong interaction the Bloch oscillation regime re-emerges with fractional Bloch periods which are inversely proportio ... [Phys. Rev. A 81, 065601 ] published .

Radio-frequency spectroscopy of Li p-wave molecules: Towards photoemission spectroscopy of a p-wave superfluid

R. A. W. Maier, C. Marzok, C. Zimmermann, and Ph. W. Courteille
We study rf spectroscopy of a lithium gas with the goal to explore the possibilities for photoemission spectroscopy of a strongly interacting p-wave Fermi gas. Radio-frequency spectra of quasibound p-wave molecules and of free atoms in the vicinity of the p-wave Feshbach resonance located at 159.15 ... [Phys. Rev. A 81, 064701 ] published .

Preparation of stable excited states in an optical lattice via sudden quantum quench

Li Wang, Yajiang Hao, and Shu Chen
We study how stable excited many-body states of the Bose-Hubbard model, including both the gaslike state for strongly attractive bosons and bound cluster state for repulsive bosons, can be produced with cold bosonic atoms in an one-dimensional optical lattice. Starting from the initial ground states ... [Phys. Rev. A 81, 063637 ] published .

Superfluid properties of ultracold fermionic atoms in two-dimensional optical lattices

Yusuke Fujihara, Akihisa Koga, and Norio Kawakami
We investigate two-component ultracold fermionic atoms with attractive interactions trapped in a two-dimensional optical lattice at zero temperature. By introducing a superfluid trial state with spatially modulated order parameters, we perform the variational Monte Carlo simulations to treat the cor ... [Phys. Rev. A 81, 063627 ] published .

Effective time-independent description of optical lattices with periodic driving

Andreas Hemmerich
For a periodically driven quantum system, an effective time-independent Hamiltonian is derived with an eigenenergy spectrum, which in the regime of large driving frequencies approximates the quasienergies of the corresponding Floquet Hamiltonian. The effective Hamiltonian is evaluated for the case o ... [Phys. Rev. A 81, 063626 ] published .

Thermometry and signatures of strong correlations from Raman spectroscopy of fermionic atoms in optical lattices

Jean-Sebastien Bernier, Tung-Lam Dao, Corinna Kollath, Antoine Georges, and Pablo S. Cornaglia
A method is proposed to directly measure the temperature of a gas of weakly interacting fermionic atoms loaded into an optical lattice. This technique relies on Raman spectroscopy and is applicable to experimentally relevant temperature regimes. Additionally, a similar spectroscopy scheme can be use ... [Phys. Rev. A 81, 063618 ] published .

Thermodynamic properties of two-component fermionic atoms trapped in a two-dimensional optical lattice

Kensuke Inaba and Makoto Yamashita
We study the finite-temperature properties of two-component fermionic atoms trapped in a two-dimensional (2D) optical lattice. We apply the self-energy functional approach to the 2D Hubbard model with a harmonic-trapping potential, and systematically investigate the thermodynamic properties of this ... [Phys. Rev. A 81, 063615 ] published .

Quantum critical behavior and trap-size scaling of trapped bosons in a one-dimensional optical lattice

Massimo Campostrini and Ettore Vicari
We study the quantum (zero-temperature) critical behaviors of confined particle systems described by the one-dimensional (1D) Bose-Hubbard model in the presence of a confining potential, at the Mott insulator to superfluid transitions, and within the gapless superfluid phase. Specifically, we consid ... [Phys. Rev. A 81, 063614 ] published .

Driven optical lattices as strong-field simulators

Stephan Arlinghaus and Martin Holthaus
We argue that ultracold atoms in strongly shaken optical lattices can be subjected to conditions similar to those experienced by electrons in laser-irradiated crystalline solids, but without introducing secondary polarization effects. As a consequence, one can induce nonperturbative multiphoton-like ... [Phys. Rev. A 81, 063612 ] published .

Noise correlations of one-dimensional Bose mixtures in optical lattices

Anzi Hu, L. Mathey, Carl J. Williams, and Charles W. Clark
We study the noise correlations of one-dimensional binary Bose mixtures, as a probe of their quantum phases. In previous work [Phys. Rev. A 80, 023619 (2009)], we found a rich structure of many-body phases in such mixtures, such as paired and counterflow superfluidity. Here we investigate the signat ... [Phys. Rev. A 81, 063602 ] published .

Superfluid-insulator transitions in attractive Bose-Hubbard model with three-body constraint

Yu-Wen Lee and Min-Fong Yang
By means of the method of the effective potential, the phase transitions from the Mott insulating state to either the atomic or the dimer superfluid state in the three-body constrained attractive Bose lattice gas are analyzed. Because of the appearance of the Feshbach resonance coupling between the ... [Phys. Rev. A 81, 061604 ] published .

Adiabatic preparation of many-body states in optical lattices

Anders S. Sorensen, Ehud Altman, Michael Gullans, J. V. Porto, Mikhail D. Lukin et al.
We analyze a technique for the preparation of low-entropy many-body states of atoms in optical lattices based on adiabatic passage. In particular, we show that this method allows preparation of strongly correlated states as stable highest energy states of Hamiltonians that have trivial ground states ... [Phys. Rev. A 81, 061603 ] published .

Reconfigurable site-selective manipulation of atomic quantum systems in two-dimensional arrays of dipole traps

J. Kruse, C. Gierl, M. Schlosser, and G. Birkl
We trap atoms in versatile two-dimensional (2D) arrays of optical potentials, prepare flexible 2D spin configurations, perform site-selective coherent manipulation, and demonstrate the implementation of simultaneous measurements of different system properties, such as dephasing and decoherence. This ... [Phys. Rev. A 81, 060308 ] published .

Quantum quenches in the anisotropic spin-[Formula: see text] Heisenberg chain: different approaches to many-body dynamics far from equilibrium

Peter Barmettler, Matthias Punk, Vladimir Gritsev, Eugene Demler, and Ehud Altman
Recent experimental achievements in controlling ultracold gases in optical lattices open a new perspective on quantum many-body physics. In these experimental setups, it is possible to study coherent time evolution of isolated quantum systems. These dynamics reveal new physics beyond the low-energy ... [New J. Phys. 12, 055017 (2010)] published Wed Jun 2, 2010.

Probing interaction-induced ferromagnetism in optical superlattices

J von Stecher, E Demler, M Lukin, and A Rey
We propose a method for controllable preparation and detection of interaction-induced ferromagnetism in ultracold fermionic atoms loaded in optical superlattices. First, we discuss how to probe and control Nagaoka ferromagnetism in an array of isolated plaquettes (four lattice sites arranged in a sq ... [New J. Phys. 12, 055009 (2010)] published Wed Jun 2, 2010.

Polar molecules with three-body interactions on the honeycomb lattice

Lars Bonnes, Hanspeter Buchler, and Stefan Wessel
We study the phase diagram of ultra-cold bosonic polar molecules loaded on a two-dimensional optical lattice of hexagonal symmetry controlled by external electric and microwave fields. Following a recent proposal in (Buchler et al 2007 Nat. Phys. 3 726), such a system is described by an extended Bos ... [New J. Phys. 12, 053027 (2010)] published Wed Jun 2, 2010.

Hofstadter butterflies in nonlinear Harper lattices, and their optical realizations

Ofer Manela, Mordechai Segev, Demetrios Christodoulides, and Detlef Kip
The ubiquitous Hofstadter butterfly describes a variety of systems characterized by incommensurable periodicities, ranging from Bloch electrons in magnetic fields and the quantum Hall effect to cold atoms in optical lattices and more. Here, we introduce nonlinearity into the underlying (Harper) mode ... [New J. Phys. 12, 053017 (2010)] published Wed Jun 2, 2010.

Anharmonicity-induced resonances for ultracold atoms and their detection

J Kestner and L-M Duan
When two atoms interact in the presence of an anharmonic potential, such as an optical lattice, the center of mass motion cannot be separated from the relative motion. In addition to generating a confinement-induced resonance (or shifting the position of an existing Feshbach resonance), the external ... [New J. Phys. 12, 053016 (2010)] published Wed Jun 2, 2010.

Electric field suppression of ultracold confined chemical reactions

Goulven Quemener and John L. Bohn
We consider ultracold collisions of polar molecules confined in a one-dimensional optical lattice. Using a quantum scattering formalism and a frame transformation method, we calculate elastic and chemical quenching rate constants for fermionic molecules. Taking KRb molecules as a prototype, we find ... [Phys. Rev. A 81, 060701 ] published .

Crossover from adiabatic to sudden interaction quenches in the Hubbard model: prethermalization and non-equilibrium dynamics

Michael Moeckel and Stefan Kehrein
The recent experimental implementation of condensed matter models in optical lattices has motivated research on their non-equilibrium behavior. Predictions about the dynamics of superconductors following a sudden quench of the pairing interaction have been made based on the effective BardeenCooperSc ... [New J. Phys. 12, 055016 (2010)] published Wed Jun 2, 2010.

Time reversal in an optical lattice

Fernando M. Cucchietti
Time reversal is an oft-used technique to probe and measure a quantum system. In particular, it is key for some theoretical information approaches to quantum criticality like fidelity decay. Here proposed is how to reverse the dynamics of cold bosonic atoms in an optical lattice in the regime descri ... [J. Opt. Soc. Am. B 27, A30 (2010)] published Wed Jun 16, 2010.

Method to Generate Complex Quasinondiffracting Optical Lattices

Servando Lopez-Aguayo, Yaroslav V. Kartashov, Victor A. Vysloukh, and Lluis Torner
We put forward a technique that allows generating quasinondiffracting light beams with a variety of complex transverse shapes. We show that, e.g., spiraling patterns, patterns featuring curved or bent bright stripes, or patterns featuring arbitrary combinations of harmonic, Bessel, Mathieu, and para ... [Phys. Rev. Lett. 105, 013902 ] published .

Nonequivalence of Ensembles for Long-Range Quantum Spin Systems in Optical Lattices

Michael Kastner
Motivated by the anisotropic long-range nature of the interactions between cold dipolar atoms or molecules in an optical lattice, we study the anisotropic quantum Heisenberg model with Curie-Weiss-type long-range interactions. Absence of a heat bath in optical lattice experiments suggests a study of ... [Phys. Rev. Lett. 104, 240403 ] published .

Probing the Fulde-Ferrell-Larkin-Ovchinnikov Phase by Double Occupancy Modulation Spectroscopy

Anna Korolyuk, Francesco Massel, and Paivi Torma
In this Letter we consider a spin-imbalanced two-component attractive Fermi gas loaded in a 1D optical lattice in the presence of an harmonic confining potential. We propose that the observation of the change in the double occupancy with respect to a lattice depth modulation can provide clear eviden ... [Phys. Rev. Lett. 104, 236402 ] published .

eta Condensate of Fermionic Atom Pairs via Adiabatic State Preparation

A. Kantian, A. J. Daley, and P. Zoller
We discuss how an eta condensate, corresponding to an exact excited eigenstate of the Fermi-Hubbard model, can be produced with cold atoms in an optical lattice. Using time-dependent density matrix renormalization group methods, we analyze a state preparation scheme beginning from a band insulator s ... [Phys. Rev. Lett. 104, 240406 ] published .

Hartree-Fock-Bogoliubov theory of dipolar Fermi gases

Cheng Zhao, Lei Jiang, Xunxu Liu, W. M. Liu, Xubo Zou et al.
We apply the Hartree-Fock-Bogoliubov theory to a system of uniform dipolar fermionic polar molecules, which recently has attracted much attention due to rapid experimental progress in achieving such systems. By calculating the anisotropic superfluid-order parameter and the critical temperature T, we ... [Phys. Rev. A 81, 063642 ] published .

Short-distance and short-time structure of a unitary Fermi gas

Dam T. Son and Ethan G. Thompson
We consider the operator product expansions for unitarity fermions. We compute the dynamic structure factor S(q,omega) at large frequency and wave number away from the one-particle peak. The overall normalization of S(q,omega) is determined by Tan's contact parameter, and the dependence on q and ome ... [Phys. Rev. A 81, 063634 ] published .

Dipolar Fermi gases in anisotropic traps

Aristeu R. P. Lima and Axel Pelster
The quest for quantum degenerate Fermi gases interacting through the anisotropic and long-range dipole-dipole interaction is an exciting and fast developing branch within the cold-atom research program. Recent experimental progress in trapping, cooling, and controlling polar molecules with large ele ... [Phys. Rev. A 81, 063629 ] published .

Equilibrium properties of trapped dipolar Fermi gases at finite temperatures

Yuki Endo, Takahiko Miyakawa, and Tetsuro Nikuni
We study the equilibrium properties of dipolar Fermi gases at finite temperatures. We introduce a variational ansatz for the phase-space distribution function that can describe the deformation in both real and momentum space. The effect of dipole-dipole interactions on thermal equilibrium is discuss ... [Phys. Rev. A 81, 063624 ] published .

Universality and stability for a dilute Bose gas with a Feshbach resonance

Yu-Li Lee and Yu-Wen Lee
We study the bosonic atoms with a wide Feshbach resonance at zero temperature in terms of the renormalization group. We indicate that this system will always collapse in the dilute limit. On the side with a positive scattering length, the atomic superfluid is an unstable local minimum in the dilute ... [Phys. Rev. A 81, 063613 ] published .

Unconventional magnetism in imbalanced Fermi systems with magnetic dipolar interactions

Benjamin M. Fregoso and Eduardo Fradkin
We study the magnetic structure of the ground state of an itinerant Fermi system of spin-1/2 particles with magnetic dipole-dipole interactions. We show that, quite generally, the spin state of particles depend on its momentum, i.e., spin and orbital degrees of freedom are entangled and taken separa ... [Phys. Rev. B 81, 214443 ] published .

Spin waves in a persistent spin-current Fermi liquid

J. D. Feldmann and K. S. Bedell
We report two theoretical results for transverse spin waves, which arise in a system with a persistent spin current. Using Fermi liquid theory, we introduce a spin current in the ground state of a polarized or unpolarized Fermi liquid, and we derive the resultant spin waves using the Landau kinetic ... [Phys. Rev. A 81, 063622 ] published .

Modified Fermi sphere, pairing gap, and critical temperature for the BCS-BEC crossover

S. Floerchinger, M. M. Scherer, and C. Wetterich
We investigate the phase diagram of two-component fermions in the BCS-BEC (Bose-Einstein condensate) crossover. Using functional renormalization-group equations we calculate the effect of quantum fluctuations on the fermionic self-energy parametrized by a wave-function renormalization, an effective ... [Phys. Rev. A 81, 063619 ] published .

Collective modes as a probe of imbalanced Fermi gases

Jonathan M. Edge and N. R. Cooper
We theoretically investigate the collective modes of imbalanced two-component one-dimensional Fermi gases with attractive interactions. This is done for trapped and untrapped systems both at zero and nonzero temperature, using self-consistent mean-field theory and the random phase approximation. We ... [Phys. Rev. A 81, 063606 ] published .

Approaching multichannel Kondo physics using correlated bosons: Quantum phases and how to realize them

Siddhartha Lal, Sarang Gopalakrishnan, and Paul M. Goldbart
We discuss how multichannel Kondo physics can arise in the setting of a localized level coupled to several bosonic Tomonaga-Luttinger liquid leads. We propose one physical realization involving ultracold bosonic atoms coupled to an atomic quantum dot, and a second, based on superconducting nanowires ... [Phys. Rev. B 81, 245314 ] published .

Pseudogap Pairing in Ultracold Fermi Atoms

Hui Hu, Xia-Ji Liu, Peter D. Drummond, and Hui Dong
The Bose-Einstein condensate to Bardeen-Cooper-Schrieffer crossover in ultracold Fermi gases creates an ideal environment to enrich our knowledge of many-body systems. It is relevant to a wide range of fields from condensed matter to astrophysics. The nature of pairing in strongly interacting Fermi ... [Phys. Rev. Lett. 104, 240407 ] published .

Verification of Universal Relations in a Strongly Interacting Fermi Gas

J. T. Stewart, J. P. Gaebler, T. E. Drake, and D. S. Jin
Many-body fermion systems are important in many branches of physics, including condensed matter, nuclear, and now cold atom physics. In many cases, the interactions between fermions can be approximated by a contact interaction. A recent theoretical advance in the study of these systems is the deriva ... [Phys. Rev. Lett. 104, 235301 ] published .

Normal Phase of an Imbalanced Fermi Gas

Christophe Mora and Frederic Chevy
Recent experiments on imbalanced Fermi gases have raised interest in the physics of an impurity immersed in a Fermi sea, the so-called Fermi polaron. In this Letter, a simple theory is devised to describe dilute Fermi-polaron ensembles corresponding to the normal phase of an imbalanced Fermi gas. An ... [Phys. Rev. Lett. 104, 230402 ] published .

Short-Time Operator Product Expansion for rf Spectroscopy of a Strongly Interacting Fermi Gas

Eric Braaten, Daekyoung Kang, and Lucas Platter
Universal relations that hold for any state provide powerful constraints on systems consisting of fermions with two spin states interacting with a large scattering length. In radio-frequency (rf) spectroscopy, the mean shift in the rf frequency and the large-frequency tail of the rf transition rate ... [Phys. Rev. Lett. 104, 223004 ] published .

Spin Drag in an Ultracold Fermi Gas on the Verge of Ferromagnetic Instability

R. A. Duine, Marco Polini, H. T. C. Stoof, and G. Vignale
Recent experiments [Jo et al., Science 325, 1521 (2009)] have presented evidence of ferromagnetic correlations in a two-component ultracold Fermi gas with strong repulsive interactions. Motivated by these experiments we consider spin drag, i.e., frictional drag due to scattering of particles with op ... [Phys. Rev. Lett. 104, 220403 ] published .

Dynamical Unbinding Transition in a Periodically Driven Mott Insulator

Fabian Hassler, Andreas Ruegg, Manfred Sigrist, and Gianni Blatter
We study the double occupancy in a fermionic Mott insulator at half filling generated via a dynamical periodic modulation of the hopping amplitude. Tuning the modulation amplitude, we describe a crossover in the nature of doublon-holon excitations from a Fermi golden rule regime to damped Rabi oscil ... [Phys. Rev. Lett. 104, 220402 ] published .

Thermalization in a quasi-one-dimensional ultracold bosonic gas

I Mazets and J Schmiedmayer
We study the collisional processes that can lead to thermalization in one-dimensional (1D) systems. For two-body collisions, excitations of transverse modes are the prerequisite for energy exchange and thermalization. At very low temperatures, excitations of transverse modes are exponentially suppre ... [New J. Phys. 12, 055023 (2010)] published Wed Jun 2, 2010.

Spontaneous creation of nonzero-angular-momentum modes in tunnel-coupled two-dimensional degenerate Bose gases

T. W. A. Montgomery, R. G. Scott, I. Lesanovsky, and T. M. Fromhold
We investigate the dynamics of two tunnel-coupled two-dimensional degenerate Bose gases. The reduced dimensionality of the clouds enables us to excite specific angular momentum modes by tuning the coupling strength, thereby creating striking patterns in the atom density profile. The extreme sensitiv ... [Phys. Rev. A 81, 063611 ] published .

Wave functions of the super-Tonks-Girardeau gas and the trapped one-dimensional hard-sphere Bose gas

M. D. Girardeau and G. E. Astrakharchik
Recent theoretical and experimental results demonstrate a close connection between the super-Tonks-Girardeau (STG) gas and a one-dimensional (1D) hard-sphere Bose (HSB) gas with hard-sphere diameter nearly equal to the 1D scattering length a of the STG gas, a highly excited gaslike state with nodes ... [Phys. Rev. A 81, 061601 ] published .

s-wave scattering of a polarizable atom by an absorbing nanowire

Martin Fink, Andres Naranjo, Florian Arnecke, Johannes Eiglsperger, Harald Friedrich et al.
We study the scattering of a polarizable atom by a conducting cylindrical wire with incoming boundary conditions, that is, total absorption, near the surface of the wire. Based on the explicit expression given recently [C. Eberlein and R. Zietal, Phys. Rev. A 75, 032516 (2007)] for the nonretarded a ... [Phys. Rev. A 81, 062714 ] published .

Phases of lattice hard-core bosons in a periodic superlattice

Long Dang and Massimo Boninsegni
We study by quantum Monte Carlo simulations the phase diagram of lattice hard-core bosons with nearest-neighbor repulsive interactions, in the presence of a superlattice of adsorption sites. For a moderate adsorption strength, the system forms crystal phases registered with the adsorption lattice; a ... [Phys. Rev. B 81, 224502 ] published .

Stochastic mean-field theory: Method and application to the disordered Bose-Hubbard model at finite temperature and speckle disorder

Ulf Bissbort, Ronny Thomale, and Walter Hofstetter
We discuss the stochastic mean-field theory (SMFT) method, which is a new approach for describing disordered Bose systems in the thermodynamic limit including localization and dimensional effects. We explicate the method in detail and apply it to the disordered Bose-Hubbard model at finite temperatu ... [Phys. Rev. A 81, 063643 ] published .

Correlations and superfluidity of a one-dimensional Bose gas in a quasiperiodic potential

Alberto Cetoli and Emil Lundh
We consider the correlations and superfluid properties of a Bose gas in an external potential. Using a Bogoliubov scheme, we obtain expressions for the correlation function and the superfluid density in an arbitrary external potential. These expressions are applied to a one-dimensional system at zer ... [Phys. Rev. A 81, 063635 ] published .

Bose gas in a single-beam optical dipole trap

Lena Simon and Walter T. Strunz
We study an ultracold Bose gas in an optical dipole trap consisting of one single focused laser beam. An analytical expression for the corresponding density of states beyond the usual harmonic approximation is obtained. We are thus able to discuss the existence of a critical temperature for Bose-Ein ... [Phys. Rev. A 81, 063620 ] published .

Relation between ac Josephson effect and double-well Bose-Einstein-condensate oscillations

Leo Radzihovsky and Victor Gurarie
In this article we comment on the relation between the ac Josephson effect and the coherent oscillations of a Bose-Einstein condensate confined to a double-well potential. The goal is to elucidate the extent to which the latter is a realization of the former. We detail the correspondence between the ... [Phys. Rev. A 81, 063609 ] published .

Dynamics of a cold atom cloud in an anharmonic trap

Andrea Bertoldi and Leonardo Ricci
A combined gravitomagnetic trap was used to measure how the anharmonicity of a trapping potential affects the dynamics of a cold atomic cloud. A displacement of the effective potential minimum as a function of the ensemble temperature was observed. The effect is a direct consequence of the thermal n ... [Phys. Rev. A 81, 063415 ] published .

Ground-state properties of few dipolar bosons in a quasi-one-dimensional harmonic trap

F. Deuretzbacher, J. C. Cremon, and S. M. Reimann
We study the ground state of few bosons with repulsive dipole-dipole interaction in a quasi-one-dimensional harmonic trap by means of the exact diagonalization method. Up to three interaction regimes are found, depending on the strength of the dipolar interaction and the ratio of transverse to axial ... [Phys. Rev. A 81, 063616 ] published .

Exact results on the two-particle Green's function of a Bose-Einstein condensate

Takafumi Kita
Starting from the Dyson-Beliaev and generalized Gross-Pitaevskii equations with an extra nonlocal potential, we derive an exact expression of the two-particle Green's function [script K][underaccent underbar [below] for an interacting Bose-Einstein condensate in terms of unambiguously defined self- ... [Phys. Rev. B 81, 214513 ] published .

Bose-Einstein Condensation in Microgravity

T. van Zoest, N. Gaaloul, Y. Singh, H. Ahlers, W. Herr et al.
Albert Einstein's insight that it is impossible to distinguish a local experiment in a freely falling elevator from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions ... [Science 328, 1540 (2010)] published Wed Jun 16, 2010.

Strongly Correlated Gases of Rydberg-Dressed Atoms: Quantum and Classical Dynamics

G. Pupillo, A. Micheli, M. Boninsegni, I. Lesanovsky, and P. Zoller
We discuss techniques to generate long-range interactions in a gas of ground state alkali atoms, by weakly admixing excited Rydberg states with laser light. This provides a tool to engineer strongly correlated phases with reduced decoherence from inelastic collisions and spontaneous emission. As an ... [Phys. Rev. Lett. 104, 223002 ] published .

Ramsey Interference in One-Dimensional Systems: The Full Distribution Function of Fringe Contrast as a Probe of Many-Body Dynamics

Takuya Kitagawa, Susanne Pielawa, Adilet Imambekov, Jorg Schmiedmayer, Vladimir Gritsev et al.
We theoretically analyze Ramsey interference experiments in one-dimensional quasicondensates and obtain explicit expressions for the time evolution of full distribution functions of fringe contrast. We show that distribution functions contain unique signatures of the many-body mechanism of decoheren ... [Phys. Rev. Lett. 104, 255302 ] published .

Criticality in Trapped Atomic Systems

L. Pollet, N. V. Prokof'ev, and B. V. Svistunov
We discuss generic limits posed by the trap in atomic systems on the accurate determination of critical parameters for second-order phase transitions, from which we deduce optimal protocols to extract them. We show that under current experimental conditions the in situ density profiles are barely su ... [Phys. Rev. Lett. 104, 245705 ] published .

Strong Charge-Transfer Excitonic Effects and the Bose-Einstein Exciton Condensate in Graphane

Pierluigi Cudazzo, Claudio Attaccalite, Ilya V. Tokatly, and Angel Rubio
Using first principles many-body theory methods (GW+Bethe-Salpeter equation) we demonstrate that the optical properties of graphane are dominated by localized charge-transfer excitations governed by enhanced electron correlations in a two-dimensional dielectric medium. Strong electron-hole interacti ... [Phys. Rev. Lett. 104, 226804 ] published .

Dipole blockade in a cold Rydberg atomic sample [Invited]

Daniel Comparat and Pierre Pillet
We review here the studies performed about interactions in an assembly of cold Rydberg atoms. We focus especially on the review of the dipoledipole interactions and on the effect of the dipole blockade in the laser Rydberg excitation, which offers attractive possibilities for quantum engineering. We ... [J. Opt. Soc. Am. B 27, A208 (2010)] published Wed Jun 16, 2010.